356 Mr. E. R. Lankester on new Mammalia 



colour, partly owing, no doubt, to the natural stain which occurs 

 in the incisors of most Rodentia. 



Delphinus {Phoccena) uncidens, n. sp. 



Of the two little teeth represented in PI. VIII. figs. 12,13, one 

 is in my own collection, the other in that of Mr. Whincopp. 

 When first I obtained these, I was led, by their peculiar curved 

 form and great length of fang, to regard them as incisors of a 

 species of Phoca, and this the more especially since a Seal had 

 been discovered by the illustrious Van Bcneden in the Antwerp 

 Crag. A careful comparison and examination of the teeth, 

 however, has convinced me that they belong to a species of 

 Delphinus hitherto undescribed. In those Seals which present 

 incisors having this peculiar hook-like form the tooth is invari- 

 ably lobed or developed to a small extent on one side; the fang, 

 too, is considerably flattened, so that the antero-postcrior breadth 

 is greater than the lateral. In the two teeth from the Crag this 

 is not the case : the unciform crown is perfectly symmetrical, 

 and the fang is flattened in the reverse direction. The form of 

 the teeth agrees very exactly with the conoid denticles of some 

 Delphinidse, more particularly of the subgenus Phoccena. The 

 enamel on the crown is thin, as in most Cetacea, whilst the en- 

 larged fang is very characteristic of that group. I propose 

 therefore to call this species Delphinus uncidens. With the teeth 

 I would associate, under this specific name, certain small ceto- 

 tolites, which have long been known as occurring in the Crag, 

 more particularly in the neighbourhood of Woodbridge (whence 

 also the teeth were originally obtained), but which have never 

 been described. One of these auditory bones is represented in 

 figs. 3, 3. Such examples are very numerous of this size, which 

 would agree very well with the size of the small teeth. They 

 are evidently the "ear-cases" of small Delphinida?, and pre- 

 sent no striking characters which should distinguish the animal 

 to which they belonged from the ordinary forms oi Phoccena and 

 Delphinus. It may be considered a very fortunate circumstance 

 that the teeth and ear-bones can thus be united, and assigned 

 to the same species in so certain a manner, since the discon- 

 nected nature of the Cetacean remains of the Red Crag has in 

 many instances prevented a correct appreciation of their specific 

 and generic value. 



Delphinus [Phoccena) orcoides, n. sp. 



The species to which I have ventured to give this name is repre- 

 sented by three teeth in the collection of Mr. Whincopp, of which 

 two are drawn in PI. VIII. figs. 14-18. At first sight, the tooth 

 in figs. 14, 15, 16 might also be mistaken for the canine of one of 



